An Overview of Sweat:

Why do humans sweat? Whether it be a slight sweat or a torrential outpouring, your body produces sweat countless times a day to regulate body temperature. Although the levels of sweat vary depending on multiple stimuli, everyone sweats. To regulate temperature, the body produces sweat, and a small amount of the body’s heat is carried onto the skin’s surface via sweat. After the sweat exits the body onto the skin, it then evaporates into the atmosphere, removing both the liquid sweat and the heat from the body. This can happen because sweat is made of water and a few other forms of bodily waste. However, why does it seem like we sweat so much more when the air is humid? It is one of those, sometimes annoying, environmental causes of excessive sweating that we all have to deal with.

How Humidity Impacts Sweat Evaporation:

Humidity is a key player in determining the amount of sweat does or does not evaporate off an individual. To start, let’s define humidity is a measure of a liquid vapor in a given volume of gas. In most instances, humidity refers to the amount of water vapor present in the atmosphere for a given area. Humidity is most commonly rated on a 0-100% scale. Air that is considered 0% humid holds no water vapor in the air, and air that is considered 100% humid holds all of the water vapor it possibly can based on the principles of environmental gases. One of these laws states that liquids and gases flow from an area of high concentration to low concentration. When there is a low amount of humidity in the air, the liquid sweat on your skin has an easy time transitioning the sweat from a liquid on your body to a gas in the atmosphere.

Sweat Evaporating off Your Skin and into the Atmosphere

When the sweat leaves your body, it takes the heat from the human body with it. This exodus of heat is what makes sweating effective at cooling the human body. However, when there is a high amount of humidity in the air, the liquid sweat on your skin has a hard time transitioning the sweat from a liquid on your body to a gas in the atmosphere. The high amount of water vapor in the atmosphere means the sweat on your skin will not leave your body and fail to be as effective in removing heat from the body. The lingering sweat on the skin in humid conditions explains why a humid day can make sweating so much worse. Many individuals feel that a day with high humidity and a temperature around 80 degrees Fahrenheit causes them to overheat and accumulate more sweat than a low humidity day with a temperature around 90 degrees Fahrenheit would. These conditions are especially hard on those with hyperhidrosis, an interesting sweat condition to know about. There are others weat conditions as well, some cause stinky sweat and others cause a person not to sweat at all.

3 tips to be Prepared for Humid Weather:

1. Check the Humidity Levels Regularly

Fortunately, humidity levels can often be predicted and monitored ahead of time. Check your local weather forecasts to see when humid conditions may be coming to an area near you.

2. Avoid the Humid Heat that Often Arrives after a Storm.

Storms often push the humidity levels to near or at 100%, and time is the best tool to let the humidity levels drop after rain.

3. Apply Antiperspirant before Entering a Humid Environment

Are you wondering if you need antiperspirant or deodorant? If you are struggling with sweat, you probably do. Not sure what antiperspirant does and how it is different than deodorant? Antiperspirant prevents sweat from forming, while deodorant only masks the smell of body odor and has some bacteria killing properties. For best results, apply the antiperspirant at least 15 minutes before entering the humid environment to give your body time to absorb the antiperspirant into your sweat glands. You can also try over-the-counter topical treatments for hyperhidrosis if you have excessive sweating in these conditions and regular antiperspirant isn’t cutting it.

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